Exercise has also been found to reduce the risk for many serious health problemsthat affect those who are overweight, including:

Coronary heart disease

Stroke

Type 2 Diabetes

Osteoporosis

High blood pressure

Depression

Physical activity will have these beneficial health effects regardless of your body weight and regardless of the weight loss result if any that you achieve from being active.

How does physical activity reduce body weight?

1) Being active burns calories, which results into a reduced total daily energy expenditure

2) Physical activity builds muscles, which take up more energy while at rest

Walking May Improve Your Immunity

A recent US study looked at the effects of a 30-minute walk on a wide range of immune function measures.

They analysed blood samples from healthy volunteers after sitting quietly for 30 minutes and after walking briskly for 30 minutes.

They found that a 30 minute walk led to positive changes in several immune system components. Whereas sitting for 30 minutes was not associated with any such beneficial changes.

This study adds to the existing bulk of evidence to show that moderate activity (activity that raises the heart rate to between 60-65% of its maximum rate) leads to positive immune changes, by increasing the number of immune-system cells in the blood.

The authors suggest that these immune changes may explain why regular moderate exercise is associated with fewer upper respiratory tract infections and consequently, fewer days off due to sickness.